U.S. patent number 4,534,538 [Application Number 06/512,083] was granted by the patent office on 1985-08-13 for modular air shut-off valve.
This patent grant is currently assigned to The United States of America as represented by the Secretary of the Air. Invention is credited to John J. Buckley, William T. Scott.
United States Patent |
4,534,538 |
Buckley , et al. |
August 13, 1985 |
Modular air shut-off valve
Abstract
A modular air shut-off valve, particularly useful within the air
conditioning environmental control system of an aircraft, is
provided, which comprises a housing sized for insertion into a duct
of the air conditioning system, a vane pivotally mounted within the
housing for pivotal movement between open and closed positions and
having flexible portions along its edges contacting the housing in
the closed position for providing a resilient seal and to allow
pressure relief in the event of overpressure within the duct.
Inventors: |
Buckley; John J. (Baltimore,
MD), Scott; William T. (Ellicott City, MD) |
Assignee: |
The United States of America as
represented by the Secretary of the Air (Washington,
DC)
|
Family
ID: |
24037598 |
Appl.
No.: |
06/512,083 |
Filed: |
July 8, 1983 |
Current U.S.
Class: |
251/62;
137/454.6; 137/527; 251/306 |
Current CPC
Class: |
F24F
13/1426 (20130101); Y10T 137/7898 (20150401); Y10T
137/7668 (20150401); F24F 2013/1466 (20130101) |
Current International
Class: |
F24F
13/14 (20060101); F16K 031/143 () |
Field of
Search: |
;137/454.2,454.6,527
;251/306,62 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Weakley; Harold W.
Attorney, Agent or Firm: Singer; Donald J. Scearce; Bobby
D.
Government Interests
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or
for the Government of the United States for all governmental
purposes without the payment of any royalty.
Claims
We claim:
1. A modular air shut-off valve configured for insertion into an
air conditioning duct, comprising:
a. a housing, including first and second pairs of confronting
sidewalls, said housing sized for insertion into said air
conditioning duct, said walls defining an inlet and an outlet at
respective ends of said housing and a passageway of substantially
rectangular cross section for passage of air through said
housing;
b. a vane mounted between said first confronting sidewall pair for
pivotal movement, about an axis intersecting each said first
sidewall pair at corresponding points between a first sidewall of
said second sidewall pair and a center line extending between said
inlet and outlet and defined along said passageway, between a
closed position at which said passageway is substantially blocked
and an open position at which said passageway is substantially
open, said vane having a first portion mounted generally between
said axis and said first sidewall of said second sidewall pair for
rotation toward said inlet in said open position, and a second
portion of area larger than said first portion mounted generally
between said axis and the second sidewall of said second sidewall
pair for rotation toward said outlet in said open position, each of
said portions having flexible margins along corresponding edges of
said vane for resiliently contacting said second sidewall pair in
said closed position; and
c. pressure actuating means connected to said vane for selectively
pivoting said vane between said open and closed positions.
2. The valve as recited in claim 1 wherein said actuating means
includes a pneumatically operated piston operatively connected to
said vane.
3. The valve as recited in claim 1 wherein said actuating means
includes a hydraulically operated piston operatively connected to
said vane.
4. The valve as recited in claim 1 wherein said flexible margins of
said vane comprise an elastomer.
5. A modular air shut-off valve configured for insertion into an
air conditioning duct, comprising:
a. a housing, including first and second pairs of confronting
sidewalls, said housing sized for insertion into said air
conditioning duct, said walls defining an inlet and an outlet at
respective ends of said housing and a passageway of substantially
rectangular cross section for passage of air through said
housing;
b. a shaft journaled at its respective ends in said first
confronting sidewall pair for rotation about an axis intersecting
said first sidewall pair between a first sidewall of said second
sidewall pair and a center line defined along said passageway
between said inlet and outlet;
c. a vane attached to said shaft for rotation therewith, between an
open position at which said passageway is substantially open and a
closed position at which said passageway is substantially closed,
said vane having a first portion mounted generally between said
shaft and said first sidewall of said second sidewall pair and a
second portion of size larger than said first portion mounted
generally between said shaft and the second sidewall of said second
sidewall pair and having flexible marginal portions along
corresponding edges thereof for resiliently contacting said second
sidewall pair in said closed position, said vane mounted for
rotation of said second portion toward said outlet in said open
position:
d. a crank attached to one end of said shaft: and
e. pressure actuating means operatively connected to said crank for
selectively pivoting said vane between said open and closed
positions by rotation of said shaft about said axis.
6. The valve as recited in claim 5 wherein said actuating means
includes a pneumatically operated piston operatively connected to
said crank.
7. The valve as recited in claim 5 wherein said actuating means is
a hydraulically operated piston operatively connected to said
crank.
8. The valve as recited in claim 5 wherein said flexible marginal
portions of said vane comprise an elastomer.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to aircraft environmental control
systems and more particularly to a novel modular air shut-off valve
for controlling airflow within an aircraft cooling air duct.
The environmental control systems of certain aircraft, though
designed to provide wholly adequate cooling airflow, during flight,
to the cockpit and to radar and various avionic systems, may not be
designed to provide sufficient cooling to all systems while the
aircraft is on the ground on a hot day. It is recognized, however,
that when the aircraft is awaiting takeoff, certain systems aboard
the aircraft may not need to be fully functional. For example, when
the aircraft is on the ground, the radar on board may function only
in a standby mode, requiring less than full cooling airflow rates
to all portions of the radar system, and therefore the cooling
airflow to some portions thereof may be closed off during this
period. The capability to control the flow of cooling air as just
stated may be essential in order to meet hot-day ground operational
requirements of the aircraft.
The present invention provides a modular air shut-off valve for use
in the ducts which supply coling air within the environmental
control system of an aircraft. The valve has found particular
application to control the flow of coolant air to the radar in
ground operation modes aboard the aircraft to satisfy
specifications for hot-day ground operation. The valve of the
present invention comprises a generally rectangularly-shaped vane
or damper, mounted on a rotatable shaft within a suitable housing
in an air conditioning duct, and having flexible marginal portions
contacting the inner surfaces of the housing in the closed
position. The vane may therefore be self-adjusting and may serve as
a relief valve in the event of overpressure in the duct containing
the valve. In the specific embodiment described herein to
illustrate a representative structure and built to demonstrate
utility of the invention, the valve was configured to control the
flow of cooling air to the radar system; the valve was controlled
pneumatically using the servo air (about 18 psig) provided by the
aircraft for the pressurization of the waveguide; power to the
pneumatic system controlling the valve was provided by a 28-volt
signal from a squat switch on the landing gear of the aircraft.
It is therefore a principal object of the present invention to
provide a modular air shut-off valve.
It is a further object to provide a modular air control valve
particularly useful within the environmental control system of an
aircraft.
These and other objects of the present invention will become
apparent as the detailed description of specific representative
embodiments thereof proceeds.
SUMMARY OF THE INVENTION
In accordance with the foregoing principles and objects of the
present invention, a modular air shut-off valve, particularly
useful within the air conditioning environmental control system of
an aircraft, is provided, which comprises a housing sized for
insertion into a duct of the air conditioning system, a vane
pivotally mounted within the housing for pivotal movement between
open and closed positions and having flexible portions along its
edges contacting the housing in the closed position for providing a
resilient seal and to allow pressure relief in the event of
overpressure within the duct.
DESCRIPTION OF THE DRAWINGS
The present invention will be more clearly understood from the
following detailed description of specific embodiments thereof read
in conjunction with the accompanying drawings wherein:
FIG. 1 is an isometric drawing, in partial cutaway of one
embodiment of the invention and illustrates the assembly thereof
with an air conditioning duct.
FIG. 2 is a schematic diagram of a pressurizing system suitable for
controlling operation of the valve of the present invention.
FIGS. 3a, 3b, and 3c are partial sectional views of the valve
illustrating operation of the vane.
DETAILED DESCRIPTION
Referring now to FIG. 1 of the drawings, shown therein is a
preferred representative configuration for the novel modular air
shut-off valve 10 of the present invention. Valve 10 is, for
clarity, shown detached from an air duct 11 of the aircraft
environmental control system into which valve 10 is configured to
be received, and is shown in substantial cutaway to expose
component parts. Duct 11 is ordinarily constructed to conduct
coolant airflow from a source (not shown) for distribution to
systems, such as the radar system, the cockpit, avionics systems,
etc., requiring air conditioning. Valve 10 comprises a housing 12
including a flanged top plate 13, sidewalls 14, 15, and bottom 16,
defining an inlet opening 17 and an outlet opening 18 at respective
ends of housing 12, substantially as shown, and a passageway for
passage of air therethrough. Housing 12 is sized to be snugly
received by an opening provided in aircraft air conditioning duct
11 as shown. In a representative configuration designed for actual
use, the overall dimensions of valve 10 were about 21/2 inches wide
by 21/2 inches long by 1 inch high. It is understood, however, that
these sizes are illustrative only as size is not limiting of the
invention herein. Housing 12 may be secured to duct 11
conventionally as by screws 19 inserted through holes 20 in the
flanged ends of top plate 13, and engaging tapped holes 21 in the
housing of duct 11. A conventional gasket 22 may be included to
provide a desired airtight seal between top plate 13 and the
surface 11a defining the opening in duct 11 for receiving valve
10.
A substantially rectangularly-shaped damper or vane 23 having
flexible top 23t and bottom 23b marginal portions is sized to fill
the cross section of the duct defined through housing 12, and is
mounted for pivotal movement about an axis A between open and
closed positions. In the closed position, as shown in FIG. 1, top
portion 23t of vane 23 flexes and resiliently seals against the
lower (inner) surface of top plate 13, and bottom portion 23b
flexes and seals against the upper (inner) surface of bottom plate
16 of housing 12 (or against the bottom of air duct 11 if housing
12 has no, or a partial, bottom 16). In a representative mounting
configuration, vane 23 may be supported on a shaft 24 journaled for
rotation at a first end into sidewall 14 of housing 12. A crank 25
is formed in, or otherwise attached to the second end of shaft 24
substantially as shown. Shaft 24 is preferably positioned for
rotation about axis A intersecting sides 14, 15 of housing 12 above
a centerline B through the duct defined by housing 12 (i.e.,
intermediate the centerline B and top 13) so that the portion of
vane 23 (including portion 23b ) below shaft 24 is somewhat larger
than that above shaft 24 (including portion 23t). The center of
pressure for air flowing through housing 12 may therefore be at a
position on vane 23 such as indicated at 26. Vane 23 may comprise
any suitable material of construction, or combination of materials,
including suitable elastomers, thin metals, molded plastics, high
durometer rubbers, polyurethanes, vinyl resins, or the like, of
suitable thickness for the purpose herein described. In a
representative valve 10 constructed in demonstration of the
invention, vane 23 was 0.010 inch thick and comprised fire
resistant epoxy fiberglass (FR4).
Pressure actuation means for controlling vane 23 position may be in
the form of a cylinder 27 defined within sidewall 15 of housing 12
substantially as shown for receiving a pressure actuated piston 28
and return spring 29 disposed to act on one end of piston 28. The
specific embodiment shown in the drawings is representative of a
pneumatic system comprising the pressure actuating means. It is
understood, however, within the scope hereof, that the actuating
means may comprise a hydraulic system. Therefore, respective
component parts shown in FIGS. 1 and 2, though described as
comprising a pneumatic system, are intended to include the
hydraulic equivalents.
A central diametric hole 30 is provided in piston 28, substantially
as shown, to receive the crank 25 on the second end of shaft 24.
The operative interconnection of crank 25 and piston 28 as
described provides for rotation of shaft 24 (and of vane 23), to
selectively block the air flowing through duct 11 and the duct
defined by housing 12 by the axial movement of piston 28 within
cylinder 27. Suitable porting or channeling 31 within wall 15
interconnects cylinder 27 with a connector 32. A mating connector
33 connected to an inlet 34 may be disposed on duct 11 to provide
the means to interconnect valve 10 with a source of pressure (not
shown in FIG. 1). It is understood that, within the intended scope
of these teachings, the location of the fittings 32, 33 and the
configuration of the channeling within wall 15 to accommodate the
fittings, may be alternatively selected.
Referring now additionally to FIG. 2, shown therein is a schematic
diagram of a representative pneumatic system interconnected with
valve 10 to provide operation of vane 23 for the control of airflow
through duct 11. Pneumatic pressure may be available from a
pressure source 35 of servo control air (nominally about 18 psig)
to supply to valve 10 through a three-way control valve 36 and air
line 37. As shown in FIG. 2, the three branches of valve 36 may be
connected, respectively, to source 35, valve 10 via line 37, and an
exhaust 38. Valve 36 may be controlled by solenoid 39 controlled
remotely by a signal or switch such as switch 40. As discussed
previously, the switch 40 may be in the form of the squat switch
actuated when the aircraft gear is down and supporting the weight
of the aircraft, but which opens (deactivates) upon takeoff and
retraction of the landing gear. Upon takeoff, solenoid valve 39
closes to vent the pneumatic pressure supplied to valve 10 via
valve 36, thereby opening valve 10 to restore airflow through duct
11.
To illustrate the principles of operation of valve 10 of the
present invention, reference is now made to FIGS. 3a, 3b, and 3c in
conjunction with FIG. 1. FIG. 3a illustrates the position vane 23
assumes in the normal (no power) configuration allowing
substantially unrestricted airflow through the duct containing vane
23 substantially as shown. Shaft 24 is mounted off (above) center
of the duct defined by housing 12, as previously described, in
order to provide sufficient aerodynamic moment to maintain vane 23
open when the pressure control mechanism illustrated in FIGS. 1 and
2 is not actuated. The coolant airflow in typical aircraft systems
for which valve 10 of this invention is intended for use is
normally about 1/2 to 2 psig, which is ordinarily adequate to
provide sufficient aerodynamic moment. Spring 29 acting on piston
28 assists in maintaining vane 23 open when the pressure actuating
system is off. It is instructive to note that, in the event of
failure of the components comprising the pressure actuating system
of FIG. 2, vane 23 will, under the action of spring 29, assume a
normal open position to allow airflow through the duct 11.
When pressure is applied to cylinder 27, as through actuation of
the system of FIG. 2, the pressure urges piston 28 against spring
29 and in so moving rotates shaft 24 by reason of the
interconnection of piston 28 and crank 25. When so actuated, vane
23 assumes the position best depicted in FIG. 3b (also illustrated
in FIG. 1) wherein the flexible ends of vane 23 are rotated to and
deflect against the top 13 and bottom 16 sides defining the duct
through housing 12, thereby closing the duct against further
airflow. The flexibility of the vane 23 also allows the piston 28
to move its full design travel without overloading the vane by the
pneumatically generated torque.
The flexibility of vane 23, and particularly of portion 23b,
provides an additional advantage of the present invention in the
event of unexpected overpressure occurring in the duct when vane 23
is closed. When a condition of overpressure occurs, portion 23b of
vane 23 may flex such as illustrated in FIG. 3c to reduce the
pressure differential across vane 23, and to preclude possible
consequent structural damage within the air conditioning system of
which duct 11 is a part. Excessive overpressure of as low as about
4 psig may be intolerable within the airflow duct 11, which
overpressure may be provided for by the function of vane 23
illustrated in FIG. 3c without compromising the desirable sealing
function at normal (lower) airflow pressure values.
The novel modular air shut-off valve of the present invention is
therefore characterized by its compactness, ease of maintenance,
reliability, and simplicity of operation; power consumption of the
related control systems is minimal during operation of the aircraft
on the ground, and no power is required during flight. The novel
flexible vane of the valve provides desirable sealing when the
valve is actuated, yet allows relief when subjected to overpressure
as might otherwise cause structural damage in the environmental
control system of the aircraft.
The present invention therefore provides a novel modular air
shut-off valve particularly useful in conjunction with the air
cooling systems aboard an aircraft, although other applications may
be made as might occur to one with skill in the applicable field.
All embodiments contemplated hereunder have therefore not been
shown in detail. Other embodiments may be developed without
departing from the spirit of the invention or from the scope of the
appended claims.
* * * * *